Well, every marker on my application will represent a user, so I need to identify that user when I click the info window to get its data from the Internet, and I can't make it identify them by name for obvious reasons. Is it possible to add an extra attribute to a marker object? thanks!
You could make a HashMap<Marker, User>
check this tutorial: http://bon-app-etit.blogspot.be/2012/12/add-informationobject-to-marker-in.html